Features: r Breathing muscle trainer regards it as a lung fitness center. It is a good product for improving aerobic exercise endurance, improving lung capacity, improving muscle endurance, reducing dyspnea, improving sleep quality, and training lungs and respiratory muscles. rUsage: The breathing trainers can adjust the size of your breathing resistance. You can adjust the resistance by turning the valves to improve your daily breathing health, increase endurance and lung capacity. rWidely used in various places such as swimming, diving, surfing, running, fitness, tourism, etc. rPreferred material: Made of high-quality silicone material, with good adhesion and sealing properties; Environmentally friendly and completely safe. rService: If you have any questions, please contact us to provide good service. rNote: r1. The actual color may be slightly different from the image due to different light effects r2. Please allow 1-3cm deviation due to manual measurement r rMaterial: SiliconeABS rSize: 62cm * 35cm * 33cm r rPackage list: rBreathing trainer*1